From The Collaborative International Dictionary of English v.0.48 :
Machinist \Ma*chin"ist\, n. [Cf. F. machiniste.]
1. A constructor of machines and engines; one versed in the
principles of machines.
[1913 Webster]
2. One skilled in the use of machine tools.
[1913 Webster]
3. A person employed to shift scenery in a theater.
[1913 Webster]
From WordNet (r) 3.0 (2006) :
machinist
n 1: a craftsman skilled in operating machine tools [syn:
machinist, mechanic, shop mechanic]